In the food and beverage industry there is a need for efficient and reliable manufacturing processes to quickly and safely manufacture and package the food and beverage product. Most food and beverage plants across the United States run continuously, 24 hours a day and 7 days a week, to meet the ever increasing demands. With these stringent demands on their machines as well as personnel, most food and beverage plants have implemented some form of process control or automation. By using programmable logic controllers (PLCs) and various other logic controlling devices, elementary applications that used to require manual attention can now be done with machines.
In particular, the demand today for beverage containers filled with product, such as cola and beer, is greater than it has ever been and continues to grow. These containers can be glass bottles, aluminum cans or any type of canister that can store, for example, consumable beverages, automobile product, hair and skin care product, and any other liquid or semi-liquid product that is packaged and distributed in such a container. These container packages can be any size and shape, such as those found in 12 ounce cola or beer cans and bottles, and the various bottles containing hair care product.
These containers can be made from many different materials, such as glass, plastic, aluminum, tin among others, and are enclosed, after being filled with product, using a type of cap or top attached by screwing onto the container, crimping, pressing or heat sealing, or in other ways to enclose the product in the container.
In order to meet this demand for liquid and semi-liquid product, high speed, automatic filling machines are incorporated in the filling process. These automatic machines can load, fill, enclose, and box up thousands of these containers each minute in a high-speed operation. These automatic filling machines load the empty containers onto a conveyor and move the bottles into a location on the machines where the containers come in contact with the filling machine and are filled with product. Once filled, the containers are enclosed or sealed and are quickly moved away from the filling station, and boxed up or packaged along with other filled containers to be shipped or distributed to retail centers and the like.
In such a high-speed operation, when an accident or mistake occurs, hundreds or thousands of containers may inadvertently be filled before the filling machine or process can be halted. In these situations, the hundreds or thousands of containers filled after the accident may need to be discarded, wasting time and money to determine which bottles were filled after the accident.
The fill process will vary depending on the product being filled, and various factors, such as the temperature and viscosity of the product, the beverage gas, the effect of those gases and related pressure characteristics during the filling process. Accordingly, the filling process and related conditions can be optimized and maximized monitoring and controlling these factors. For purposes of this application and for simplicity, most of the examples herein will refer to a carbonated beverage filling process, although the apparatus, system and methods described herein relate to any similar type of filling process.
Further, the filling process can not alter the food or beverage being filled. Thus, when planning a filling system it is important to match the appropriate filling steps to the beverage characteristics and container. The steps of the filling process include some or all of the following: evacuation of the container, flushing the container with gas, pressurizing the container with gas, filling the container with one or multiple speeds, fill level correction (in certain cases), and settling the product.
Evacuation is used mostly on rigid containers in which a vacuum process removes upwards of 90% of the air content in the container prior to pressurizing with gas. Evacuation becomes more important when the contents being filled are oxygen sensitive and the may be repeated at other times throughout the filling process. Additionally or alternatively, the container may be flushed with gas. This is done mostly with flexible containers, such as PET bottles and aluminum cans, which may not be able to withstand a vacuum. The flushing step takes place at the time that the fill valve is located at the container and usually uses gas from the filling ring bowl until both pressures are the same.
Next, filling takes place when the fill valve opens and the product flows over and around the vent tube and into the container. As the container fills, gas in the containers is displaced by the product and flows through the vent tube and out of the container into the filler ring bowl, until the container is full. As an example, the vent tube may contain an electronic probe to detect product and stop filling. Accordingly, the vent tube vents the gases being used while filling the container with fluid. The process needs to be extremely accurate, and as a result most vent tubes are designed at specific lengths to achieve each specific fill level per filling machine.
Fill level correction may be incorporated when the cost of product is high to save product. In the most commonly used fill level correction step, the container is first overfilled with product and then the product is extracted using a vacuum through the vent tube. Finally, by settling, the pressure in the container is lowered and the beverage is allowed to settle as it is lowered from the fill valve.
The vent tubes used in the filling process described above usually are configured with an elongated, hollow, cylindrical tube extending the length of the tube which allows the vent tube to enter the container opening during the fill process without touching the container. As described above and in U.S. Pat. No. 3,736,966, which is incorporated by reference herein, the product can flow over the vent tube into the container. The lower tip of the vent tube is usually closed and one or more holes are provided so that any gas or air in the container can be displaced through the vent tube during the filling process, minimizing or eliminating the possibility of a container exploding during filling
Traditionally, filling machines for glass containers use a vent tube made of stainless steel or a stainless food-grade plastic hybrid. For filling aluminum containers, the vent tube is usually made from some form of food-grade plastic, such as Delrin®. Vent tubes can also use a ball and cage system as described in U.S. Publication No. U.S.20050199314 A1, which is incorporated by reference herein.
In certain instances, the high speed automatic filling machines allow for removing and replacing the vent tube or a portion of the vent tube, such as the cap, as described in U.S. Pat. Nos. 4,049,030 and 5,878,797, which are incorporated by reference herein. In other situations, a removable vent tube cap or tip can be attached, either by using threads on the cap, a slot, a snap-in configuration or some other manner, as understood by one having ordinary skill in the art.
Due to the high speeds and constant use of these filling machines, occasionally a vent tube may detach from the filling machine and fall into the product container. When this event occurs there are minimal systems in place to halt the filling process, locate the detached vent tube or portion thereof (such as a cap), repair the filling machine and begin the process again. Each minute that the process is halted equates to thousands of unfilled containers, as filling machines can run at speeds of 1650 cans per minute. Further, the longer the process continues, the more filled containers that will have to be examined to find the detached vent tube. In many situations, the containers filled with product that were boxed up or packaged after the vent tube became detached are merely discarded, increasing the costs of the accident.
Some of the current systems used to check for detached stainless steel vent tubes include the use of inductive or capacitive sensors, vision systems or other ultrasonic inline systems. Additionally, systems for determining when a vent tube has become detached and fallen into the container include the electromagnetic detection fields or X-ray based technologies. Some of the manufactures of these technologies include Omron Corporation, Industrial Dynamics Company, and the Fortress Technology Inc., among others.
However, most of these inspection systems need to have direct access to each and every container after it has been filled with product, and are used as a way to detect the vent tube by examining each container. This process either slows down the filling line because each and every container must be examined, or takes longer time than necessary to find the container in which the vent tube has fallen if each container has not been examined.
Further, some of the systems work better with metal vent tubes, while other systems work better with plastic vent tubes creating inconsistencies, or the need for additional equipment when changing to different vent tubes. For example, when a plastic vent tube falls into a can made of aluminum at a filling plant, the inductive and capacitive technologies cannot detect the plastic vent tube (foreign) object through the aluminum can.
There is currently no apparatus, system or method that incorporates an indicator, such as an RFID tag or a magnet, into a vent tube or a replaceable vent tube cap for use during filling operations, that increases the safety of the filling operation and reduces the costs and time when a malfunction occurs, such as when a vent tube detaches from the filling machine and falls into the container. There is also no apparatus, system or method relating to vent tubes or vent tube caps incorporating an RFID tag or a magnet that allows for a quicker and more accurate determination of the location of a vent tube that has become detached from a filling machine during filling operations. The present disclosure satisfies these needs.